package com.bella.springcloud.lb;/**
 * @program: cloud2022
 * @description:
 * @packagename: com.bella.lb
 * @author: Bella白
 * @date: 2022-09-01 23:32
 **/

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @author: bella白
 * @Title: MyLB
 * @ProjectName: cloud2022
 * @Description:
 * @date: 2022/9/1 23:32
 */
@Component
public class MyLB implements LoadBanlancer {

    private AtomicInteger atomicInteger = new AtomicInteger(0);

    public final int getAndIncrement(){
        int current;
        int next;
        do{
            current=this.atomicInteger.get();
            next = current>=2147483647 ? 0 : current+1;//2147483647整型的最大值Interger.MAX_VALUE -2^31-2^31-1
        }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("****第几次访问的次数 next:"+next);
        return next;
    }
    @Override
    public ServiceInstance instance(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement()%serviceInstances.size();
        return serviceInstances.get(index);
    }
}
